[3/3] usb: dwc3: Support option to disable USB2 LPM

[Felipe Balbi <balbi@kernel.org>]

Hi,

Felipe Balbi <balbi@kernel.org> writes:
>>> --- a/drivers/usb/dwc3/core.h
>>> +++ b/drivers/usb/dwc3/core.h
>>> @@ -971,6 +971,7 @@ struct dwc3_scratchpad_array {
>>>   * @setup_packet_pending: true when there's a Setup Packet in FIFO. Workaround
>>>   * @three_stage_setup: set if we perform a three phase setup
>>>   * @usb3_lpm_capable: set if hadrware supports Link Power Management
>>> + * @usb2_lpm_disable: set to disable usb2 lpm
>>>   * @disable_scramble_quirk: set if we enable the disable scramble quirk
>>>   * @u2exit_lfps_quirk: set if we enable u2exit lfps quirk
>>>   * @u2ss_inp3_quirk: set if we enable P3 OK for U2/SS Inactive quirk
>>> @@ -1146,6 +1147,7 @@ struct dwc3 {
>>>         unsigned                setup_packet_pending:1;
>>>         unsigned                three_stage_setup:1;
>>>         unsigned                usb3_lpm_capable:1;
>>> +       unsigned                usb2_lpm_disable:1;
>>
>> Hi,
>>
>> that may be a bit late, but why would this be a property of dwc3?
>> Now, you may want to do this for a specific controller,
>> but there is no reason to limit the flag to dwc3. We want this
>> flag in the generic HCD attributes, so that other HCDs can share
>> it. Maybe even expose it to sysfs.
>
> this is used for the peripheral side of dwc3 too.

oh, and this is exposed through dwc3's private registers, not the
generic XHCI registers.